No nothing at all, except that I did have a crash early this morning and the
only way to recover was to pull the plug and release the battery. It worked
fine again for 4 hours then the freezing and fading started.

I ran the Computer Janitor (or did you mean inside the casing?) a few weeks
ago and got rid of some stuff, memory was a bit low so I moved a bunch of
pdf's and films onto DVD's.

I recently switched off for a while and restarted, no change.